Meaning of the word "that's that" in English

What does "that's that" mean in English? Explore the meaning, pronunciation, and specific usage of this word with Lingoland.

that's that

US /ðæts ðæt/
UK /ðæts ðæt/
"that's that" picture

Phrase

used to say that a situation is finished and will not be changed

Example:
I've made my decision, and that's that.
The meeting is over, that's that.